First of all, note this song is a gospel song, written as a kind of dirge. So there is a religious context, and it's somewhat mournful, as if it is about death and dying.
The rest of the lyrics list various kinds of sinners -- friends who lie, who seek drama (or possibly divine retribution), who "mislead the pure", who "sin just for fun", and so on. Wonder says "they won't go when I go" -- possibly meaning they won't go to Heaven. But in that case it ought to be "They won't go where I go", so your guess is as good as mine. Although, in the final stanza, you have "The kingdom I will see". "Kingdom" pretty much means "Heaven".
Anyway all of that is important to judging what Wonder means by the second of the two lines you quote. The first is pretty obvious, but the second "wanting tragic ends" could mean "people consciously or unconsciously seeking death" or it could refer to judgmental people who want tragic death for other people. Or it could just mean people who want things that will lead to general tragedy.
I don't think it much matters to the overall theme of the song, which again, seems to me a gospel tune about how the righteous will go to Heaven.